The present invention relates to telephone call fee notifying system and an apparatus in an exchange system including a mobile terminal such as a personal handyphone.
The conventional charging system can be classified into major two types of which one asks only a calling (originating) subscriber for payment of a telephone call fee and the other asks a called (terminating) subscriber to pay a telephone call fee. JP-A-4-54057 discloses a system in which a called subscriber can freely change the charging index. In this system, when a control signal for changing the charging index is transmitted from the called subscriber following completion of talking, a telephone call fee which has been charged on a calling subscriber is so changed as to be charged on the called subscriber or vice versa, thus making it possible to select a charging system meeting a request of the called subscriber.
With the conventional systems, however, charging of a telephone call fee is controlled from only the called subscriber and the contents or amount of charging can be known only by the called subscriber. Accordingly, in spite of the fact that a telephone call fee may be extraordinarily higher for, for example, mobile terminal communications than for the ordinary wire telephone, this fact may be forgotten by the caller and talking is done as if an ordinary wire telephone is used, with the result that an unexpectedly high telephone call fee is charged later on. But means for knowing the telephone call fee is not provided on the calling subscriber side and therefore it is not possible for the calling subscriber to decide to make the call by taking the telephone call fee into account even when an urgent communication is desired.